Motivation

I wanted to be able to tell users all of the devices they were logged in on, and I wanted the information being displayed to be as accurate as possible.

While looking for a solution, I learned that using just a user agent string was not enough and neither was using just client hints.

For more information, see https://github.com/ua-parser/uap-core/issues/452

Why Is Using Just a User Agent String Not Enough?

Sometimes browsers identify themselves in their Sec-CH-UA header but not their user agent string. Brave is an example of this (except for the iOS version, which does not send Sec-CH-UA or Sec-CH-UA-Platform headers).

Why Is Using Just Client Hints Not Enough?

Sometimes browsers identify themselves in their user agent string but not their Sec-CH-UA header. The Android version of Ecosia is an example of this (its Sec-CH-UA header says that it is Chromium). In addition, some browsers do not send Sec-CH-UA or Sec-CH-UA-Platform headers.

Installation

pip install identify_browser

Usage

from identify_browser import identify_browser

# These values could come from anywhere. For example, in Django, they could come from:
#
# request.headers.get("User-Agent", "")
# request.headers.get("Sec-Ch-Ua", "")
# request.headers.get("Sec-Ch-Ua-Platform", "")
user_agent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36"
sec_ch_ua = '"Not/A)Brand";v="8", "Chromium";v="126", "Brave";v="126"'
sec_ch_ua_platform = '"Windows"'

browser_identity = identify_browser(user_agent, sec_ch_ua, sec_ch_ua_platform)
print(f"You appear to be using {browser_identity['name']} {browser_identity['version']} on {browser_identity['platform']}")
# Output: You appear to be using Brave 126 on Windows